1. Field of the Invention
The present invention relates to a device for treatment of plantar fascitis, acute ankle sprains, acute gastrocnemius strains, Achilles tendonitis, tendon repair, foot drop, or any other condition or injury relating to foot or ankle pain.
More particularly, the present invention relates to an affordable multifunctional device that provides a passive dorsiflexion vector force on the foot and ankle through the metatarsalphalangeal joints by keeping the foot in a neutral to slightly dorsiflexed position, while at rest.
2. Description of the Related Art
In this specification where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of the common general knowledge or known to be relevant to an attempt to solve a problem with which this specification is concerned.
In the sole of one's foot is a thick fibrous material called the plantar aponeurosis or fascia. The plantar fascia is a thick fibrous material that covers the soft tissue on the sole of the foot, providing static support for the medial longitudinal arch of the foot and dynamic shock absorption. The plantar fascia originates at the heel, more specifically, at the medial tuberosity of the calcaneus, and spreads out over the sole of the foot. It terminates in the ligaments near the metatarsal heads in the forefoot. It helps to restrain motion within the joints of the ankle foot.
The plantar fascia can become inflamed as a result of stress caused by overuse and can result in conditions such as heel spurs. Heel spurs typically develop as an abnormal growth in the front and bottom of the heel bone due to calcium deposits that form when the plantar fascia pulls away from the heel. Initially, sufferers commonly experience a dull intermittent pain in the heel, which may develop into a sharp persistent pain. But it is not the spur that causes pain. The pain is caused by inflammation of the plantar fascia (known as plantar fascitis). The classic sign of plantar fascitis is heel pain with the first few steps in the morning. The pain is usually in the front and bottom of the heel, but it can be over any portion of the bottom of the foot where the plantar fascia is located. The pain varies in intensity from person to person and it can last a few months, become permanent, or come and go. Striking of the heel on the ground can exacerbate the symptoms, but is not a cause of the inflammation.
Causes of subsequent inflammation of the plantar fascia include inadequate flexibility in the calf muscles, lack of arch support or sole cushioning in footwear, footwear that has inflexible soles, being overweight, previous injuries, sudden increase in physical activity, and spending too much time on the feet. Other causes of inflammation of the plantar fascia include arthritis, heel bone damage or stress fracture, loss of natural tissue for cushioning under the heel or fat pad atrophy, and tarsal tunnel syndrome.
The key to proper treatment of plantar fascitis is a determination of what is causing the excessive stretching of the plantar fascia. However in many cases, finding a specific cause is difficult. Typically, plantar fascitis is treated using a mixture of approaches as appropriate to the sufferer. These include losing weight, the use of orthotics, increasing cushioning in the sole of shoes, resting the foot, applying supporting tape and wearing of night splints. Application of ice often helps to reduce pain although many sufferers find it necessary to use analgesics such as ibuprofen cream that can be applied directly to painful areas. In more severe cases, injections of anti-inflammatory agents may be used. Stretching the calf muscles using exercises that do not re-injure the fascia is a cure for many people. Typically, these exercises are performed 3 times a day and especially before getting out of bed in the morning. Surgery may be necessary in extreme cases of plantar fascitis.
Orthotic based treatment for plantar fascitis include elevating the heel with the use of a heel cradle or heel cup. Heel cradles and heel cups provide extra comfort and cushion to the heel, and reduce the amount of shock and shear forces experienced from everyday activities. When the cause of plantar fascitis is over-pronation (flat feet), an orthotic with rear foot posting and longitudinal arch support is an effective device to reduce the over-pronation, and allow the condition to heal. Most individuals sleep with their feet in a plantar flexed position causing the plantar fascia to rest, and therefore heal in a shortened position. A neutral, not plantar flexed, position would be optimal for healing.
Currently, there are a number of rigid devices that maintain the foot and ankle in a neutral to slightly dorsiflexed position. Furthermore, there are semi-rigid devices that provide the same function, but with less force. Of course, soft and semi-rigid devices are easier to sleep in, and have increased user compliance, but these devices have limitations in their use. Also, they overstretch the foot intrinsic and toe flexors instead of providing a plantar fascia stretch. These devices are used to treat or conservatively manage pain, muscular imbalances, and soft tissue restrictions in the foot and/or lower leg.
Many different devices have been developed to treat plantar fascitis, particularly plantar fascitis caused by heel spur. One such device for treatment of plantar fascia is described in U.S. Pat. No. 5,399,155 (Strassburg et al) and consists of an over the calf sock having a reinforced adjustable support strap attached around the upper portion of the sock with a “D” ring attached to the front (shin) side. A reinforced inelastic adjustable strap is attached to the toe of the sock, with a hook and loop assembly attached for closure. When this strap is passed through the “D” ring and secured by means of the hook and loop assembly, the plantar fascia can be maintained in the desired position. One of the disadvantages of this type of device, and many other orthotic devices, is that they only address either ankle dorsiflexion or to extension, not both.
Thus, a plantar flexion prevention device solving the aforementioned problems is desired.